Power supply systems are pervasive in many electronic applications from computers to automobiles. Generally, voltages within a power supply system are generated by performing a DC-DC, DC-AC, and/or AC-DC conversion by operating a switch loaded with an inductor or transformer. One class of such systems includes switched mode power supplies (SMPS). An SMPS is usually more efficient than other types of power conversion systems because power conversion is performed by controlled charging and discharging of the inductor or transformer and reduces energy lost due to power dissipation across resistive voltage drops.
An SMPS usually includes at least one switch and an inductor or transformer. Some specific topologies include buck converters, boost converters, and flyback converters, among others. A control circuit is commonly used to open and close the switch to charge and discharge the inductor. In some applications, the current supplied to the load and/or the voltage supplied to the load is controlled via a feedback loop.
For example, a buck converter is a specific typology used to step down an input voltage through controlled switching. The inductor is repeatedly charged and discharged such that the voltage supplied to a load is kept at a level below the input voltage. During switching, the controller connected to and supplying the control signals for the switches operates while monitoring various system parameters. Such parameters may be used to calculate feedback control and switching signals. For example, some controllers monitor output voltage or output current and alter switching parameters, such as duty cycle, in order to achieve a specific output voltage or output current.